Input interfaces in conventional electronic devices can be a keyboard, mouse, touch panel and other physical devices for the user to operate, but with advances in image-recognition technology, some electronic devices can use the camera to recognize a user's gestures or actions, and perform a corresponding operation. However, the computations required to operate such image recognition is quite heavy, and the reaction time of the electronic devices is usually not quick enough.
In addition, most gesture-control applications capture images via the camera on the electronic device, such as the camera on the top of the notebook display. However, the camera is set at a normal angle, and the image detection range of the camera is quite limited. Therefore, it is difficult to determine the user's gestures when the gesturing of the user is close to the electronic device.